Merge branch 'linus' into tracing/hw-breakpoints

Conflicts:
	arch/x86/Kconfig
	arch/x86/kernel/traps.c
	arch/x86/power/cpu.c
	arch/x86/power/cpu_32.c
	kernel/Makefile

Semantic conflict:
	arch/x86/kernel/hw_breakpoint.c

Merge reason: Resolve the conflicts, move from put_cpu_no_sched() to
              put_cpu() in arch/x86/kernel/hw_breakpoint.c.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 218 insertions, 30 deletions

diff --git a/drivers/s390/char/sclp.c b/drivers/s390/char/sclp.c
index 4377e93a43d7..a983f5086788 100644
--- a/drivers/s390/char/sclp.c
+++ b/drivers/s390/char/sclp.c
@@ -1,11 +1,10 @@
 /*
- *  drivers/s390/char/sclp.c
- *     core function to access sclp interface
+ * core function to access sclp interface
  *
- *  S390 version
- *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
- *    Author(s): Martin Peschke <mpeschke@de.ibm.com>
- *		 Martin Schwidefsky <schwidefsky@de.ibm.com>
+ * Copyright IBM Corp. 1999, 2009
+ *
+ * Author(s): Martin Peschke <mpeschke@de.ibm.com>
+ *	      Martin Schwidefsky <schwidefsky@de.ibm.com>
  */
 
 #include <linux/module.h>
@@ -16,6 +15,9 @@
 #include <linux/reboot.h>
 #include <linux/jiffies.h>
 #include <linux/init.h>
+#include <linux/suspend.h>
+#include <linux/completion.h>
+#include <linux/platform_device.h>
 #include <asm/types.h>
 #include <asm/s390_ext.h>
 
@@ -47,6 +49,16 @@ static struct sclp_req sclp_init_req;
 static char sclp_read_sccb[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
 static char sclp_init_sccb[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
 
+/* Suspend request */
+static DECLARE_COMPLETION(sclp_request_queue_flushed);
+
+static void sclp_suspend_req_cb(struct sclp_req *req, void *data)
+{
+	complete(&sclp_request_queue_flushed);
+}
+
+static struct sclp_req sclp_suspend_req;
+
 /* Timer for request retries. */
 static struct timer_list sclp_request_timer;
 
@@ -84,6 +96,12 @@ static volatile enum sclp_mask_state_t {
 	sclp_mask_state_initializing
 } sclp_mask_state = sclp_mask_state_idle;
 
+/* Internal state: is the driver suspended? */
+static enum sclp_suspend_state_t {
+	sclp_suspend_state_running,
+	sclp_suspend_state_suspended,
+} sclp_suspend_state = sclp_suspend_state_running;
+
 /* Maximum retry counts */
 #define SCLP_INIT_RETRY		3
 #define SCLP_MASK_RETRY		3
@@ -211,6 +229,8 @@ sclp_process_queue(void)
 	del_timer(&sclp_request_timer);
 	while (!list_empty(&sclp_req_queue)) {
 		req = list_entry(sclp_req_queue.next, struct sclp_req, list);
+		if (!req->sccb)
+			goto do_post;
 		rc = __sclp_start_request(req);
 		if (rc == 0)
 			break;
@@ -222,6 +242,7 @@ sclp_process_queue(void)
 						 sclp_request_timeout, 0);
 			break;
 		}
+do_post:
 		/* Post-processing for aborted request */
 		list_del(&req->list);
 		if (req->callback) {
@@ -233,6 +254,19 @@ sclp_process_queue(void)
 	spin_unlock_irqrestore(&sclp_lock, flags);
 }
 
+static int __sclp_can_add_request(struct sclp_req *req)
+{
+	if (req == &sclp_suspend_req || req == &sclp_init_req)
+		return 1;
+	if (sclp_suspend_state != sclp_suspend_state_running)
+		return 0;
+	if (sclp_init_state != sclp_init_state_initialized)
+		return 0;
+	if (sclp_activation_state != sclp_activation_state_active)
+		return 0;
+	return 1;
+}
+
 /* Queue a new request. Return zero on success, non-zero otherwise. */
 int
 sclp_add_request(struct sclp_req *req)
@@ -241,9 +275,7 @@ sclp_add_request(struct sclp_req *req)
 	int rc;
 
 	spin_lock_irqsave(&sclp_lock, flags);
-	if ((sclp_init_state != sclp_init_state_initialized ||
-	     sclp_activation_state != sclp_activation_state_active) &&
-	    req != &sclp_init_req) {
+	if (!__sclp_can_add_request(req)) {
 		spin_unlock_irqrestore(&sclp_lock, flags);
 		return -EIO;
 	}
@@ -254,10 +286,16 @@ sclp_add_request(struct sclp_req *req)
 	/* Start if request is first in list */
 	if (sclp_running_state == sclp_running_state_idle &&
 	    req->list.prev == &sclp_req_queue) {
+		if (!req->sccb) {
+			list_del(&req->list);
+			rc = -ENODATA;
+			goto out;
+		}
 		rc = __sclp_start_request(req);
 		if (rc)
 			list_del(&req->list);
 	}
+out:
 	spin_unlock_irqrestore(&sclp_lock, flags);
 	return rc;
 }
@@ -560,6 +598,7 @@ sclp_register(struct sclp_register *reg)
 	/* Trigger initial state change callback */
 	reg->sclp_receive_mask = 0;
 	reg->sclp_send_mask = 0;
+	reg->pm_event_posted = 0;
 	list_add(&reg->list, &sclp_reg_list);
 	spin_unlock_irqrestore(&sclp_lock, flags);
 	rc = sclp_init_mask(1);
@@ -880,20 +919,134 @@ static struct notifier_block sclp_reboot_notifier = {
 	.notifier_call = sclp_reboot_event
 };
 
+/*
+ * Suspend/resume SCLP notifier implementation
+ */
+
+static void sclp_pm_event(enum sclp_pm_event sclp_pm_event, int rollback)
+{
+	struct sclp_register *reg;
+	unsigned long flags;
+
+	if (!rollback) {
+		spin_lock_irqsave(&sclp_lock, flags);
+		list_for_each_entry(reg, &sclp_reg_list, list)
+			reg->pm_event_posted = 0;
+		spin_unlock_irqrestore(&sclp_lock, flags);
+	}
+	do {
+		spin_lock_irqsave(&sclp_lock, flags);
+		list_for_each_entry(reg, &sclp_reg_list, list) {
+			if (rollback && reg->pm_event_posted)
+				goto found;
+			if (!rollback && !reg->pm_event_posted)
+				goto found;
+		}
+		spin_unlock_irqrestore(&sclp_lock, flags);
+		return;
+found:
+		spin_unlock_irqrestore(&sclp_lock, flags);
+		if (reg->pm_event_fn)
+			reg->pm_event_fn(reg, sclp_pm_event);
+		reg->pm_event_posted = rollback ? 0 : 1;
+	} while (1);
+}
+
+/*
+ * Susend/resume callbacks for platform device
+ */
+
+static int sclp_freeze(struct device *dev)
+{
+	unsigned long flags;
+	int rc;
+
+	sclp_pm_event(SCLP_PM_EVENT_FREEZE, 0);
+
+	spin_lock_irqsave(&sclp_lock, flags);
+	sclp_suspend_state = sclp_suspend_state_suspended;
+	spin_unlock_irqrestore(&sclp_lock, flags);
+
+	/* Init supend data */
+	memset(&sclp_suspend_req, 0, sizeof(sclp_suspend_req));
+	sclp_suspend_req.callback = sclp_suspend_req_cb;
+	sclp_suspend_req.status = SCLP_REQ_FILLED;
+	init_completion(&sclp_request_queue_flushed);
+
+	rc = sclp_add_request(&sclp_suspend_req);
+	if (rc == 0)
+		wait_for_completion(&sclp_request_queue_flushed);
+	else if (rc != -ENODATA)
+		goto fail_thaw;
+
+	rc = sclp_deactivate();
+	if (rc)
+		goto fail_thaw;
+	return 0;
+
+fail_thaw:
+	spin_lock_irqsave(&sclp_lock, flags);
+	sclp_suspend_state = sclp_suspend_state_running;
+	spin_unlock_irqrestore(&sclp_lock, flags);
+	sclp_pm_event(SCLP_PM_EVENT_THAW, 1);
+	return rc;
+}
+
+static int sclp_undo_suspend(enum sclp_pm_event event)
+{
+	unsigned long flags;
+	int rc;
+
+	rc = sclp_reactivate();
+	if (rc)
+		return rc;
+
+	spin_lock_irqsave(&sclp_lock, flags);
+	sclp_suspend_state = sclp_suspend_state_running;
+	spin_unlock_irqrestore(&sclp_lock, flags);
+
+	sclp_pm_event(event, 0);
+	return 0;
+}
+
+static int sclp_thaw(struct device *dev)
+{
+	return sclp_undo_suspend(SCLP_PM_EVENT_THAW);
+}
+
+static int sclp_restore(struct device *dev)
+{
+	return sclp_undo_suspend(SCLP_PM_EVENT_RESTORE);
+}
+
+static struct dev_pm_ops sclp_pm_ops = {
+	.freeze		= sclp_freeze,
+	.thaw		= sclp_thaw,
+	.restore	= sclp_restore,
+};
+
+static struct platform_driver sclp_pdrv = {
+	.driver = {
+		.name	= "sclp",
+		.owner	= THIS_MODULE,
+		.pm	= &sclp_pm_ops,
+	},
+};
+
+static struct platform_device *sclp_pdev;
+
 /* Initialize SCLP driver. Return zero if driver is operational, non-zero
  * otherwise. */
 static int
 sclp_init(void)
 {
 	unsigned long flags;
-	int rc;
+	int rc = 0;
 
 	spin_lock_irqsave(&sclp_lock, flags);
 	/* Check for previous or running initialization */
-	if (sclp_init_state != sclp_init_state_uninitialized) {
-		spin_unlock_irqrestore(&sclp_lock, flags);
-		return 0;
-	}
+	if (sclp_init_state != sclp_init_state_uninitialized)
+		goto fail_unlock;
 	sclp_init_state = sclp_init_state_initializing;
 	/* Set up variables */
 	INIT_LIST_HEAD(&sclp_req_queue);
@@ -904,27 +1057,17 @@ sclp_init(void)
 	spin_unlock_irqrestore(&sclp_lock, flags);
 	rc = sclp_check_interface();
 	spin_lock_irqsave(&sclp_lock, flags);
-	if (rc) {
-		sclp_init_state = sclp_init_state_uninitialized;
-		spin_unlock_irqrestore(&sclp_lock, flags);
-		return rc;
-	}
+	if (rc)
+		goto fail_init_state_uninitialized;
 	/* Register reboot handler */
 	rc = register_reboot_notifier(&sclp_reboot_notifier);
-	if (rc) {
-		sclp_init_state = sclp_init_state_uninitialized;
-		spin_unlock_irqrestore(&sclp_lock, flags);
-		return rc;
-	}
+	if (rc)
+		goto fail_init_state_uninitialized;
 	/* Register interrupt handler */
 	rc = register_early_external_interrupt(0x2401, sclp_interrupt_handler,
 					       &ext_int_info_hwc);
-	if (rc) {
-		unregister_reboot_notifier(&sclp_reboot_notifier);
-		sclp_init_state = sclp_init_state_uninitialized;
-		spin_unlock_irqrestore(&sclp_lock, flags);
-		return rc;
-	}
+	if (rc)
+		goto fail_unregister_reboot_notifier;
 	sclp_init_state = sclp_init_state_initialized;
 	spin_unlock_irqrestore(&sclp_lock, flags);
 	/* Enable service-signal external interruption - needs to happen with
@@ -932,11 +1075,56 @@ sclp_init(void)
 	ctl_set_bit(0, 9);
 	sclp_init_mask(1);
 	return 0;
+
+fail_unregister_reboot_notifier:
+	unregister_reboot_notifier(&sclp_reboot_notifier);
+fail_init_state_uninitialized:
+	sclp_init_state = sclp_init_state_uninitialized;
+fail_unlock:
+	spin_unlock_irqrestore(&sclp_lock, flags);
+	return rc;
 }
 
+/*
+ * SCLP panic notifier: If we are suspended, we thaw SCLP in order to be able
+ * to print the panic message.
+ */
+static int sclp_panic_notify(struct notifier_block *self,
+			     unsigned long event, void *data)
+{
+	if (sclp_suspend_state == sclp_suspend_state_suspended)
+		sclp_undo_suspend(SCLP_PM_EVENT_THAW);
+	return NOTIFY_OK;
+}
+
+static struct notifier_block sclp_on_panic_nb = {
+	.notifier_call = sclp_panic_notify,
+	.priority = SCLP_PANIC_PRIO,
+};
+
 static __init int sclp_initcall(void)
 {
+	int rc;
+
+	rc = platform_driver_register(&sclp_pdrv);
+	if (rc)
+		return rc;
+	sclp_pdev = platform_device_register_simple("sclp", -1, NULL, 0);
+	rc = IS_ERR(sclp_pdev) ? PTR_ERR(sclp_pdev) : 0;
+	if (rc)
+		goto fail_platform_driver_unregister;
+	rc = atomic_notifier_chain_register(&panic_notifier_list,
+					    &sclp_on_panic_nb);
+	if (rc)
+		goto fail_platform_device_unregister;
+
 	return sclp_init();
+
+fail_platform_device_unregister:
+	platform_device_unregister(sclp_pdev);
+fail_platform_driver_unregister:
+	platform_driver_unregister(&sclp_pdrv);
+	return rc;
 }
 
 arch_initcall(sclp_initcall);